Results from a Phase II Study of Lenalidomide Oral Monotherapy in Relapsed/Refractory Indolent Non-Hodgkin's Lymphoma.

Abstract

Background: Indolent non-Hodgkin's lymphoma (NHL) has a median survival as long as 10 years but is rarely cured. Lenalidomide (Revlimid®), an immunomodulatory drug, is approved in the US for treatment of myelodysplastic syndromes associated with a del[q5] cytogenetic abnormality and is approved both in the US and the EU for the treatment of relapsed/refractory multiple myeloma. Lenalidomide also has activity in chronic lymphocytic leukemia and cutaneous T-cell lymphoma.Aim: This study was designed to assess the safety and efficacy of lenalidomide monotherapy in patients with relapsed/refractory indolent NHL.Methods: Patients with relapsed/refractory indolent NHL with measurable disease ≥ 2cm after at least 1 prior treatment regimen were eligible. Patients received 25 mg lenalidomide orally once daily on Days 1–21 every 28 days and continued therapy for 52 weeks as tolerated or until disease progression. Response and progression were evaluated using the IWLRC methodology.Results: Forty-three patients were enrolled in the study and included in this analysis. The median age was 63 (43–89) and 17 were female. Histology was small lymphocytic lymphoma [SLL] (n=18), follicular center lymphoma grades 1, 2 [FCL] (n=22), nodal marginal B-cell lymphoma (n=2) and extranodal marginal zone B-cell lymphoma of MALT type (n=1). Median time from diagnosis to lenalidomide treatment was 4.5 (0.4–24) years and median number of prior treatment regimens was 3 (1–15). Eleven of the 43 patients (26%) exhibited an objective response (2 complete responses (CR), 1 complete response unconfirmed (CRu), 8 partial responses (PR)), 15 had stable disease (SD), 13 had progressive disease (PD) and 4 were not evaluated. Responses included 4/18 SLL (22%) and 7/22 FCL (32%). Median time to response was 3.6 months (range 1.7–4.1). Progression free survival is 4.6 months for all patients, > 7.7 months (range 4.4 - > 13.5) for responding patients and ongoing. Sixteen patients (37%) required at least one dose reduction with a median time to first dose reduction of 2 months (0.5–9.6). The most common Grade 4 adverse event was neutropenia (14%) and the most common Grade 3 adverse events were neutropenia (21%) and thrombocytopenia (12%).Conclusion: Lenalidomide oral monotherapy is active with manageable side effects in relapsed/refractory indolent NHL.